Relationship of maximum follicular size, age of woman, and reproductive implications in women attending fertility clinic in St. Margaret's Hospital, Lokoja, using Creighton Model FertilityCare™ System and NaProTECHNOLOGY

Francis Udoka Achebe

doi:10.4103/NJGP.NJGP_9_18

ORIGINAL ARTICLE

Year : 2019 | Volume : 17 | Issue : 2 | Page : 51-63

Relationship of maximum follicular size, age of woman, and reproductive implications in women attending fertility clinic in St. Margaret's Hospital, Lokoja, using Creighton Model FertilityCare™ System and NaProTECHNOLOGY

Francis Udoka Achebe
Department of General Practice, St. Margaret's Hospital and Maternity, Lokoja, Kogi State, Nigeria

Date of Web Publication

8-Jul-2019

Correspondence Address:
Dr. Francis Udoka Achebe
Department of General Practice, St. Margaret's Hospital and Maternity, Felele Phase 1, Lokoja, Kogi State
Nigeria

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/NJGP.NJGP_9_18

Abstract

Background: Some authorities have found that, when the mean follicular diameter is >25 mm, the follicle is considered large, and these authorities are convinced that large follicles are biomarkers to ovarian pathology. Several studies have been carried out to determine the optimal maximum follicular size (MFS) that will be adequate before the use of human chorionic gonadotropin trigger to induce ovulation. None of these studies have considered the woman's age as a factor. An in vitro fertilization-based study has also shown that large leading follicles did not result in higher percentage of matured oocytes, and they even result in a lower live birth rate; however, we note that the ages of the women were not specifically mentioned in connection with the problems of large follicle. Subjects and Methods: We set out in this study to evaluate the relationship between the MFS and the woman's age both in our control group (fertile women) Group (A) and in the women attending fertility clinic Group (B). Using the Creighton Model Fertility Care System and NaProTECHNOLOGY, it was possible to determine when to start follicular tracking and also determine ultrasound diagnosis of ovulation by recording the MFS and the reduced size. Results: In both Group A and Group B, we discovered that the MFS reduces as woman's age increases. We also discovered that the average MFS in the Group B was higher for age compared with the Group A (P = 0.0043). There was also an association between these bigger follicles for age and low mid-luteal progesterone. This is probably the first study that describes the association of follicular size and woman's age and its possible link with ovulation defects. Recommendation: We have proposed that this phenomenon of large matured maximum follicle for age could be a contributory factor to infertility and miscarriages. We propose further studies to verify this hypothesis. Conclusion: Despite the high percentage of complete rupturing of follicles in the AB cycles in the Group (B) there are very high proportion having low mid luteal (P+7) Progesterone. This may be due to pathologies associated with big follicles for woman's age. The E2/Pg ratio study in luteal phase strongly suggested that the women in Group (B) that may have fertility challenge are those in subgroup of AB in Group (B). Therefore matured follicular size should be considered with the woman's age. If the follicles grows bigger away from the range for a woman's age it may be the marker for infertility or reproductive health challenges.

Keywords: Creighton Model FertilityCare™ system, infertility, maximum follicular size, NaProTECHNOLOGY, ovulation, woman's age

How to cite this article:
Achebe FU. Relationship of maximum follicular size, age of woman, and reproductive implications in women attending fertility clinic in St. Margaret's Hospital, Lokoja, using Creighton Model FertilityCare™ System and NaProTECHNOLOGY. Niger J Gen Pract 2019;17:51-63

How to cite this URL:
Achebe FU. Relationship of maximum follicular size, age of woman, and reproductive implications in women attending fertility clinic in St. Margaret's Hospital, Lokoja, using Creighton Model FertilityCare™ System and NaProTECHNOLOGY. Niger J Gen Pract [serial online] 2019 [cited 2023 Jun 5];17:51-63. Available from: https://www.njgp.org/text.asp?2019/17/2/51/262254

Introduction

Professor Hilgers, although did not specifically mention the correlation of “follicular size for age,” reported a case of a 30-year-old woman, gravida 0 and para 0, who during ultrasound tracking of follicular growth got a maximum follicular size (MFS) of 31.4 mm, and he judged such follicle to be too large and unhealthy; he said that the average-size follicle prior to rupture (mean follicular diameter [MFD]) is 22 mm. When the MFD is >25 mm, the follicle is considered large, and he proposes that large follicles may be biomarkers to ovarian pathology.^[1] In a study by Ojengbede et al., normal volunteers had MFS at an average of 20.8 mm (15.5–27.0) mm, and this was not significantly different from the infertile women with MFS at an average of 21.4 mm (15–28) mm;^[2] we note that the ages of these women were not considered specifically. In an intrauterine insemination study by Palatnik et al., studying the optimal follicular size before human chorionic gonadotropin (HCG) trigger in clomid and letrozole treatment cycles and pregnancy outcomes, the authors concluded that the higher pregnancy rates were achieved when the leading follicles were in the range of 23–28 mm;^[3] they did not reveal the maternal ages in which those MFSs were attained and pregnancy was achieved. A significant reduction in follicle density and percentage of morphologically normal follicles was detected with increasing age. Reduced fertility with maternal aging has been well documented in humans.^[4] We then believe that conducting a study to specifically look into the relationship of MFS prior to ovulation in relation to woman's age both in fertile women and women attending fertility hospital will be a good means of understanding the dynamism of ovulation with age. In NaProTECHNOLOGY (NPT), the mid-luteal progesterone is accurately done to confirm the ovulation by checking the Peak + 7 estrogen and progesterone levels (accurate mid-luteal progesterone assessment).^[5] Some studies have shown that increased aromatase activity is associated with increasing follicular growth beyond the antral stage. The largest follicle has the highest intrafollicular levels of estrogen due to its high capacity of androgen aromatization.^[6],[7] Estrogen has mitogenic and growth-stimulating effects on matured follicles under the influence of follicle-stimulating hormone (FSH).^[8] The aim of our study is to find out what relationship the MFS before ovulation has with woman's age, comparing our normal controls with women attending fertility Clinic and also comparing their hormonal values with the Omaha standard values.

Subjects and Methods

Creighton Model FertilityCare™ System (CrMS) and NPT are simple technologies that can be used to assess female fertility. They were used in the evaluation of relationship between MFS and age of woman, comparing controls and those attending Fertility Clinic in St. Margaret's Hospital Lokoja from 2014 to 2017; the results are interpreted on the background of standard Creighton Model chart.

Subjects

Group A (control)

Group A constituted women with normal fertility. Their hormonal profile was compared with normal fertility study data of 57 women studied at Pope Paul VI Institute for the Study of Human Reproduction [Table 3]a, [Table 3]b and [Table 5]a, [Table 5]b, [Table 5]c, [Table 5]d. They were all regularly ovulating. A total of nine women were recruited and 15 cycles were studied. Their age ranged from 23 to 45 years. They were taught how to chart the CrMS and they were all charting the CrMS fertility chart at the time of study. The participants gave verbal consent to the study. There was no financial inducement.

Group B (women attending fertility clinic)

These women were recruited into the study because they presented to be evaluated for fertility. Note that these women were not classified as being infertile. The criterion that qualified them to be in Group B was that they presented for fertility evaluation. They all desired pregnancy. They were taught how to chart the CrMS and they were all charting the CrMS fertility chart at the time of study. One of the women became pregnant during the evaluation cycle. Thirty-seven women were recruited and 37 cycles were studied. Their age ranged from 25 to 46 years. Their hormonal profile was compared with normal fertility study data of 57 women studied at Pope Paul VI Institute for the Study of Human Reproduction [Table 4]a, [Table 4]b and [Table 5]a, [Table 5]b, [Table 5]c, [Table 5]d. All the women signed the CrMS consent form which allows their data to be used in research studies. There was no financial inducement.

Ethical clearance certificate was provided by the Director of Medical Services and Training, Kogi State Ministry of Health, after the proposal of the study was sent in for approval.

The methods used to evaluate the women in Group A and Group B included the following:

Analysis of the charting pattern of the CrMS after they have been taught and developed confident identification of peak day. We paid attention to the biomarkers, namely cycle length, prepeak phase, postpeak phase, and peak day
Targeted hormonal assay: periovulatory estrogen to identify E-2, PE2, and E + 2 and postovulatory estrogen and progesterone at P + 3, P + 5, P + 7, P + 9, and P + 11, [Figure 1], [Figure 2], [Figure 3], [Figure 4] and [Table 3]a, [Table 3]b, [Table 4]a, [Table 4]b, [Table 5]a
Targeted serial ultrasound scanning: Transabdominal starting from P − 6, P − 4, P − 2, P, and P + 2 to identify the dominant follicle and follow it until it ruptures. The MFS and the reduced follicular size (RFS) were calculated by (L + B + T)/3 = MFD [Table 1]a and [Table 2]a
In the control Group (A), we plotted a graph of the MFS (Y-axis) against the age of the women (X-axis) and connected the highest follicular size attained by the youngest woman to the highest follicular size attained by the oldest woman. We now used the graph developed as our standard to compare with the women in Group (B) that presented for fertility evaluation [Figure 5]
AB = Cycle in which the MFS was matured but above the graph drawn line for age in the control
BL = Cycle in which the MFS was matured but below the graph drawn line for age in the control
OL = Cycle in which the MFS was matured and on the graph line drawn for age in the control.

Figure 1: This schematic drawing of the Creighton Model FertilityCare System demonstrates how it is used to target the periovulatory and postovulatory hormone profiles

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Figure 2: These normal values apply only to the laboratory methods used at the National Hormone Laboratory of the Pope Paul VI Institute. The E2 profile is obtained by drawing E2 levels every other day from P − 5 (or P − 6) through P + 2 (with reference to the CREIGHTON MODEL Fertility Care TM System), obtained from the endocrine evaluation of 57 spontaneous cycles which were sonographically identified as containing a mature follicle with a positive cumulus oophorus and complete rupture (anatomically normal ovulation by ultrasound). The E2 sum is obtained by adding the E2 values in the E2 profile to include the level before the peak level, the peak level and the level after the peak level (3 value sum) or the two levels before the peak level, the peak level and the level after the peak level (4 value sums). The E2 mean is the average of the 3 (3 value) or 4 (4 value) levels that are used to make up the 3- and 4-value sums. SD = Standard deviation. From: Hilgers TW: The Medical and Surgical Practice of NaProTechnology. Pope Paul VI Institute Press, Omaha, Nebraska, 2004

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Figure 3: These normal values apply only to the laboratory methods used at the National Hormone Laboratory of the Pope Paul VI Institute. Obtained from the endocrine evaluation of 57 spontaneous cycles which were sonographically identified as containing a mature follicle with a positive cumulus oophorus and complete rupture (anatomically normal ovulation by ultrasound). From: Hilgers TW: The Medical and Surgical Practice of NaProTechnology. Pope Paul VI Institute Press, Omaha, Nebraska, 2004

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Figure 4: The postpeak Estrogen from the study of 57 normal ovulating women with evidence of Cumulus oophorus and follicular rupture ≥7.5 mm

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Figure 5: Graph of the MFS (y-axis) against the age of the women (x-axis) and connecting the highest follicular size attained by the youngest woman in control (A) to the highest follicular size attained by the oldest woman in control (A). Follicles above the drawn line are in Zone AB, follicles below the line are in Zone BL. Follicles that fall on the line are in Zone OL

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Creighton Model FertilityCare System and NaProTECHNOLOGY

[Figure 6]a shows a typical Creighton Model chart. This chart is developed by the women after they have attended a fertility class (introductory session [IS]), conducted by a well-trained fertility care practitioner (FCP). This IS lasts between 4 and 6 hours depending on the size of each class and the various questions that arise from the class. Almost all women >98% will be able to start immediately to observe their various biological markers (biomarkers) and represent them on their chart from the very 1^st day of attending the “IS.” The biomarkers are observed at the vaginal outlet using flat toilet tissues to wipe the vaginal outlet from the urethra, through the vagina to the perineal body (front to back). The times to make observations included at urination, at defecation, and at bathing before and after. There is also the last observation to be made at the end of the day when the woman bears down gently and do the final wiping. These observations are very easy and the FCP will give the necessary motivation, while the husbands support their wives. Various stamps with different color codes are given to the women and they use the stamps accordingly based on what they observe on a daily basis. The “RED” stamp is to mark days of bleeding, which will include menstrual flow, or any other bleeding event that may occur. Any day she sees blood MUST have RED stamp irrespective of what day in her cycle it occurred. The numbers 1–35 on the top of the chart represent the days of cycle and not the days of the month. Immediately below the stamp space is the location for writing the date of the month. For example, if a woman starts her menses on December 27, then day 1 on the chart will be dated December 27 and day 2 will be December 28. And immediately below the date space is the space for recording of the observation using the code of the Vaginal Discharge Recording System [Figure 6]b.

Figure 6: (a) The relationship of serum levels of estradiol-17 beta and progesterone during the course of the menstrual cycle and the occurrence of the mucus sign and the peak day (P) in one cycle of a woman with normal fertility. (b) The Vaginal Discharge Recording System is at the back of the Creighton Model FertilityCare System chart that clients are given at the fertility centers after attending “IS.” These coded representations of the various vaginal discharges are well understood by women after they have been instructed by a trained fertility care practitioner

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A well-trained FCP and a NaPro medical consultant can interpret this code to generate a standardized objective evaluation from a subjective vulva observation. Once the menses starts again, she moves down to start a new cycle. The “Plain Green” stamps are used to mark the days the woman experience dryness; for example in [Figure 6]a, she has dryness from 9^th to 13^th days of her cycle in the pre-peak phase (follicular phase) and dryness from 20^th to 29^th days of her cycle in the postpeak phase (luteal phase) of her cycle. In principle, prepeak phase (days 1–19) is from the 1^st day of menstrual flow up until including the peak day. While the postpeak phase (days 20–29) is from the 1^st day after the peak day till the last day before the beginning of the next menstrual period. The CrMS study has revealed that the postpeak phase is relatively constant in length (12 days ± 4), whereas the prepeak phase is variable in length. The peak day is defined as the last day of the observation of cervical mucus discharge at the vulva that is clear, stretchy, or lubricative. Each time the woman observes mucus, she has to use the “White Baby” stamps. And, the mucus could be a peak type or nonpeak type. Peak-type mucus is either stretchy in consistency, clear in color, or lubricative in sensation. Any one of these qualities qualifies the mucus as peak type. While the nonpeak-type mucus is the mucus discharge that is not clear, not stretchy, and not lubricative. The “Green Baby” stamps are special stamps used to indicate the period after the peak day when the cervix is closing with dryness but still fertile. The NPT study has shown that the cervix closes over 3 days after the peak. The period of ovulation occurs 95.4% from peak −2 to peak +2. Ovulation is always 100% completed at peak ±3.^[9] The cervical mucus which the woman observes is a reflection of the response of the cervix to the estrogen which the developing follicles produce. And, the NPT has developed a standardized scoring system for the mucus which women observe.^[10],[11] The grading of the mucus scores is as follows: regular 9.1–16; intermediate regular 7.6–9.0; intermediate limited 5.7–7.5; limited 0.1–5.6; and dry = 0. To calculate this mucus score, we start from the peak day and count six steps backward. All the mucus observed on these days (P − 5), + (P − 4), + (P − 3), + (P − 2), + (P − 1), + (peak day) are calculated and the sum is divided by 6. The mucus is scored on four characteristics (3CS), namely: (1) consistency (length of mucus), 6 and 8 are both scored 2. The mucus that is stretchy coded 10 is scored 4. (2) color, mucus that is brown, cloudy, or yellow is scored 2, the mucus that is crystal clear, transparent, is scored 4. (3) change, no change in mucus scored 2, and change in mucus scored 4. (4) sensation, The mucus that feels nonlubricative is scored 0, and the mucus that feels lubricative is scored 4. Any day that mucus was not observed is scored 0. For example 1: 8CL means tacky, cloudy, and lubricative. The score; consistency, 8 scored (2), colour, cloudy is scored (2), Changed to Lubricative scored (4), Sensation is Lubricative scored 4. Total = 2 + 2 + 4 + 4 = 12. Example 2: 10 C means stretchy, cloudy. The score; Consistency, 10 scored (4), color, cloudy is scored (2), Changed to nonlubricative scored (2), sensation nonlubricative scored (0). Total = 4 + 2 + 2 + 0 = 8. The sperm survival in the cervical mucus is very important in natural reproductive medicine and so limited or dry mucus scores are associated with some form of fertility challenge.

The schematic representation in [Figure 1] is what is used in NPT to target when to collect blood samples for hormonal assays to determine the periovulatory Estrogen levels, and postovulatory estrogen and progesterone. The way to do accurate targeting is to first look at the previous complete chart the woman has made, for example the chart in [Figure 6]a, above. Identify the peak day and count backward from the peak-1 to peak-6. In [Figure 6]a, the peak day is on the 19^th day of the cycle, therefore 6-steps backwards will be day 13^th. Then in the new cycle which the woman will make prospectively, the 13^th day will be peak-6, 15^th day will be peak-4, 17^th day will be peak-2, 19^th day will be peak day, and 21^st day will be peak +2. And, in all these days, blood will be collected for periovulatory estrogen assessment. Also, it is on those days that targeted ultrasound will be done for follicular tracking. During ultrasound pay attention to measuring the length, breath, and transverse diameters of the developing follicle and calculate the MFD = (L + B + T)/3 in mm or cm. Also, pay attention to identify the presence or absence of cumulus oophorus. By the time you get to the predicted peak +2 in the cycle of evaluation, the woman would have identified the peak day in that very cycle. And with the peak day identified, we can then identify the days for peak +3, +5, +7, +9, and +11 for the collection of postovulatory blood samples for estrogen and progesterone. The effectiveness of this method to target the hormones accurately is 96.9%.^[12] The normal range used in this study was from a study done on 57 women at the Pope Paul VI Institute for the Study of Human Reproduction in Omaha USA. They were all regularly ovulating with positive cumulus complex present in matured follicles (18–26 mm).^[13] In all ultrasound diagnosed ovulation, the follicular rupture is complete with follicular rupture difference (FRD) ≥7.5 mm. The assumption in the study at Omaha was that since these 57 women had satisfactory ultrasound diagnosed ovulation of matured follicles with positive cumulus complex, they also therefore must correspond with normal periovulatory estrogen, and postovulatory (postpeak) estrogen and progesterone values.

Based on this graph in [Figure 5], the simplified working data for maximum matured follicle size in “mm” for age at which HCG trigger could be given to induce follicular rupture included the following:

23 Yr(24.9), 24 Yr(24.7), 25 Yr(24.5), 26 Yr(24.2), 27 Yr(24.0), 28 Yr(23.8), 29 Yr(23.6), 30 Yr(23.5), 31 Yr(23.3), 32 Yr(23.1), 33 Yr(23.0), 34 Yr(22.8), 35 Yr(22.5), 36Yr(22.4), 37 Yr(22.2), 38 Yr(22.0), 39 Yr(21.7), 40 Yr(21.5), 41 Yr(21.3), 42 Yr(21.0), 43 Yr(20.8), 44 Yr(20.5), 45 Yr(20.3), 46 Yr(20.0), 47 Yr(19.8), 48 Yr(19.6), 49 Yr(19.4), 50 Yr(19.0).

Conversion to IS units:

Estrogen: ng/dl × 10 = pg/ml; pg/ml × 3.671 = pmol/ml
Progesterone: nmol/l × 0.314 = ng/ml; ng/ml × 3.18 × 1000 = pmol/ml.

Presentations of Results

The results of the study are presented in [Table 1]a, [Table 1]b, [Table 2]a, [Table 2]b, [Table 3], [Table 3]a, [Table 3]b, [Table 4]a, [Table 4]b, [Table 5]a, [Table 5]b, [Table 5]c, [Table 5]d and [Figure 5].

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Discussion

From [Table 1]a, the Control Group (A), a total of 15 cycles were studied. And, a total of 15 follicles were also studied. Moreover, based on NPT classification of ultrasound ovulation diagnosis, only one follicle did not reach the minimum matured size of 19.0 mm,^[14] it was 18.8 mm, but was considered matured by Ojengbede et al.^[2] All the cycles were regular cycles ranging from 25 to 30 days. The age ranges was from 23 to 45 years with a mean age of 30.5 years; standard deviation (SD) 7.76. The maximum matured follicles ranges from 18.8 to 24.9 mm, with a mean size of 20.6 mm, SD 1.62. Standard graph was drawn using data from the control group to develop the Zone ABove the line (AB), the Zones On the maximum Line (OL), and the Zones BeLow the line (BL). The size of the maximum matured follicles was on the Y-axis, while the age of the women was on the X-axis [Figure 5]. In the Control Group (A), 13 cycles recorded the matured MFS below the line (BL) (86.7%); and 2 cycles recorded the matured MFSs on the control line (OL) (13.3%). We also noticed that the maximum matured follicular size synchronized with the peak periovulatory estrogen (PE2) 100% of the time. Our study from the fertile control Group (A) seems to suggest that large matured follicles are good for younger women, and smaller size matured follicles are good for older women.

In NPT, ovulation defects could be diagnosed based on FRD [Figure 7]. A complete follicular rupture is when the FRD is ≥7.5 mm. Calculating FRD is done by this formula: (MFS − RFS = FRD). From [Table 1]a, ten cycles (66.7%) had complete follicular rupture, while five cycles (33.3%) had partial rupture syndrome (PRS). Details of the periovulatory estrogen and postovulatory progesterone at peak +7 are summarized in [Table 1]b, [Table 3]a, [Table 3]b, and [Table 5]a.

Figure 7: This shows the various ovulation defects that could be diagnosed by ultrasound in NaProTECHNOLOGY grow bigger away from the range for a woman's age, it may be the marker for infertility or reproductive health challenges.

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Out of the 13 cycles that are BL, 9 (69.2%) had normal periovulatory estrogen, and out of these 9, 6 (66.7%) had high mid luteal (P + 7) progesterone with associated 100% complete follicular rupture, while the remaining 3 (33.3%) had normal mid luteal (P + 7) progesterone with associated 66.7% PRS, and 33.3% complete rupture.

Four of the BL cycles (30.8%) had high periovulatory estrogen, and out of these four, one (25%) had high mid luteal (P + 7) progesterone with associated 100% complete follicular rupture, while the remaining three (75%) had normal mid luteal (P + 7) progesterone with associated 100% PRS.

Out of the two cycles that are OL, one had high periovulatory estrogen, while the other had normal periovulatory estrogen. They both had high mid luteal (P + 7) progesterone and both associated with complete follicular rupture.

From the control Group (A), complete follicular rupture seems to be associated with high mid luteal progesterone outcomes while PRS seems to be associated with normal mid luteal (P + 7) progesterone irrespective of whether the periovulatory estrogen was high or normal [Table 1]b.

Among the women attending Fertility Clinic, Group (B), a total of 37 cycles were studied. All the cycles were regular cycles ranging from 24 to 31 days. The ages ranged from 25 to 46 years, with a mean age of 33.7 years, SD 4.84. The matured MFSs ranges from 18.0 to 31.1 mm, with a mean size of 22.4 mm, SD 3.19. The mean MFS in the women attending fertility clinic Group (B) of 22.4 mm is significantly bigger (P = 0.0043) compared to the control Group (A) with mean MFS of 20.6 mm. We also noted that the average age of the control Group (A) of 30.5 year was not statistically different from the average age of the Group (B) of 33.7 years (P = 0.075).

In Group (B) 37 cycles was studied in 37 women attending fertility clinic. One woman had two follicles that matured and completely ruptured and therefore a total of 38 follicles were studied. Using the graph in [Figure 5] we found out that the 38 follicles studied in these 37 women fell into 3 categories; Group B (AB) 14 cycles (36.8%), Group B (BL) 23 cycles (60.5%), and Group B (OL) one cycle (2.6%). Of the 38 follicles studied, 5 did not attain NPT minimum matured size of 19.0 mm (they were 16.9, 17.7, 18.0, 18.9, 18.9),^[14] but they are considered matured based on the Ojengbede et al. studies.^[2] Complete follicular rupture occurred in 30 follicles (78.9%), and PRS occurred in 8 follicles (21.1%). Details of the periovulatory estrogen and postovulatory progesterone at peak +7 were studied in [Table 2]a, [Table 4]a, [Table 4]b and [Table 5]a.

Out of the 14 cycles that are AB cycles in Group (B), 12 (85.7%) had high periovulatory estrogen, and out of these, 8 (66.7%) had low mid luteal (P + 7) progesterone with associated 87.5% complete follicular rupture, and 12.5% PRS; while the remaining 4 (33.3%) had normal mid luteal (P + 7) progesterone with associated 75% complete follicular rupture, and 25% PRS.

One cycle of AB (7.1%) out of the 14 cycles had normal periovulatory estrogen with a normal mid luteal (P + 7) progesterone and associated complete follicular rupture. And one cycle of AB (7.1%) out of the 14 cycle had low periovulatory estrogen with a low mid luteal (P + 7) progesterone with associated complete follicular rupture.

Despite the high percentage of complete rupturing of follicles in the AB cycles, there is very high proportion having low mid luteal (P + 7) progesterone. This may be due to pathologies associated with big follicles for woman's age. And also, high periovulatory estrogen in these big follicles seems to contribute to their large size. There is a possibility that cumulus complex defect may be associated as shown in ovulation defect studies by Hilgers.^[15]

Out of 23 cycles that are BL cycle in Group (B), 11 (47.8%) had high periovulatory estrogen, and out of these, 6 (54.5%) had normal mid luteal (P + 7) progesterone with associated 83.3% complete follicular rupture, and 16.7% PRS; while the remaining 5 (45.5%) had low mid luteal (P + 7) progesterone with associated 80% PRS and 20% complete rupture.

Out of the 23 cycles that are BL in Group (B), 9 (39.1%) had normal periovulatory estrogen, and out of these, 5 (55.6%) had normal mid luteal (P + 7) progesterone with associated 100% complete follicular rupture; and another 3 (33.3%) had low mid luteal (P + 7) progesterone with associated 100% complete follicular rupture; and the last one cycle (11.1%) had high mid luteal (P + 7) progesterone with associated complete follicular rupture. (We expected the three follicles [33.3%] with normal periovulatory estrogen and 100% complete rupture to have at least normal mid luteal [P + 7] progesterone but they had low values. These follicles may be empty follicles without cumulus. Further research is needed to get better insight of what happened).

Out of the 23 cycles that are BL in Group (B), 3 (13.0%) had low periovulatory estrogen, and out of these, 2 (66.7%) had low mid luteal (P + 7) progesterone with associated 50% complete rupture, and 50% PRS; and one cycle (33.3%) had low periovulatory estrogen, and normal mid luteal (P + 7) progesterone with associated complete follicular rupture.

In the BL cycles in Group (B) with either high or normal periovulatory estrogen, complete rupture leads to normal mid luteal (P + 7) progesterone while PRS lead to low mid luteal (P + 7) progesterone.

In the Group (B) women, only one cycle (2.6%) was OL. And, this cycle had normal periovulatory estrogen, with low mid luteal (P + 7) progesterone with associated complete rupture. We expected this follicle to have at least normal mid luteal progesterone but it is possible that the size has already started to have adverse effect on the follicular function and cumulus complex defect may also be involved. Further research is needed to get deeper insight.

We must note that in NPT, ovulation defects is also considered with regards with the presence or absence of cumulus complex in a follicle, and also even examined if the cumulus complex was released or retained after rupture event.^[15] We did not look into cumulus complex study because of limitation to do the very technical ultrasound involved. So it is a possibility that some of the matured follicles in the Group (B) may also have cumulus challenges resulting in poor luteal progesterone. Further research in this regard is needed.

In [Table 3], studying the Group (B), the distribution of AB, BL, OL, by age ranges showed that the cycles recording AB dominated 60% only among age range 34–36 years. From the study, we noted that AB cycle can occur from ages 28 to 42 years, and it is important to be vigilant about this in managing client during fertility assessment.

The hormonal assay results both for periovulatory estrogen and postovulatory estrogen and progesterone in Group A and subgroups namely Group A (BL) and Group A (OL) and in Group B and subgroups namely Group B (BL), Group B (OL), and Group B (AB) are all presented in [Table 3]a, [Table 3]b, [Table 4]a, [Table 4]b, and [Table 5]a. The statistical study of these hormones and how they were compared with the Omaha study are reported in [Table 5]a, [Table 5]b, [Table 5]c, [Table 5]d.

In [Table 5]a, the control Group A and Group B, with all their subgroups had high periovulatory estrogen sum of 3-values compared to the Omaha study, but none reached statistical significance.

In [Table 5]b, both the Group A (P = 0.000296) and Group B (P = 0.000189) had significantly increased luteal phase estrogen sum of 5-values compared to Omaha study.

In [Table 5]c, Group A (P = 0.0017) had significant increase in luteal phase progesterone sum of 5-values; while the Group B (P = 0.059) had reduced luteal phase progesterone sum of 5-values but was not statistically significant compared to the Omaha study. However, the Group B reduced luteal phase progesterone sum of 5-values was compared with the Group A control, the reduction was very significant (P = 0.0022).

In [Table 5]d, the estrogen/progesterone ratio (E2/Pg) was studied for Group A, and subgroups namely; Group A (BL), Group A (OL), and Group B and subgroups namely; Group B (BL), Group B (OL), Group B (AB). Note that the estrogen unit was (pg/ml), and progesterone unit was (ng/ml). The study of E2/Pg ratio is a better assessment of the luteal phase status rather than just checking the individual hormones. A high E2/Pg ratio indicates estrogen dominance in the luteal phase, while a low E2/Pg ratio indicates progesterone dominance in luteal phase. Estrogen dominance in luteal phase is associated with narrow or closed implantation window. According to a study published in the Proceedings of the National Academy of Science of the United States of America, “the window of uterine receptivity remains open for an extended period at lower estrogen levels but rapidly closes at higher estrogen levels.”^[16] Looking at the statistic in [Table 5]d, we noticed that Group B (AB) had the most significant estrogen dominance in luteal phase. The Group B (BL) did not show statistical significance in increase in the E2/Pg ratio compared to Omaha study or to Group A control. This shows that the women in this group had relatively favorable implantation window compared to those in Group B (AB). It is important to note that the 26-year-old woman in Group B (BL) cycle 15, had a MFS of 24 mm and she conceived in the cycle of her evaluation!

Conclusion

In both the control group (Group A) and the women attending Fertility Clinic (Group B), we discovered that the MFS reduces as the woman's age increases. We also discovered that the average MFS in the Group (B) (22.4 mm) was higher, with P = 0.0043, compared with the control Group (A) (20.6 mm). Our study from the fertile control Group (A) and the Group (B) women seem to suggest that large matured follicles are healthy for younger women, and smaller size matured follicles are healthy for older women. In an in vitro fertilization (IVF) study by Jaime et al., they discovered that large leading follicles do not yield a higher percentage of matured oocytes, and they even resulted in a lower, albeit not significant so, live birth rate.^[17]

From the control Group (A), complete follicular rupture was associated with high mid luteal progesterone outcomes while PRS was associated with normal mid luteal (P + 7) progesterone irrespective of whether the periovulatory estrogen was high or normal. These suggest that the cumulus complex activities in these normal controls are functioning well, but further study is needed to understand the phenomenon better.

Despite the high percentage of complete rupturing of follicles in the AB cycles in the Group (B) there are very high proportion having low mid luteal (P + 7) progesterone. This may be due to pathologies associated with big follicles for woman's age. And also, high periovulatory estrogen in these big follicles seems to contribute to their large size. Possibility of cumulus complex defect association should be considered.^[15]

In the BL cycles, among the Group (B) with either high or normal periovulatory estrogen, complete rupture leads to normal mid luteal (P + 7) progesterone while PRS lead to low mid luteal (P + 7) progesterone. This was not what was observed in the BL cycles in the control Group (A). Therefore, the PRS cases in the Group (B) may also have associated cumulus complex defects leading to the low mid luteal (P + 7) progesterone.

The E2/Pg ratio study in luteal phase strongly suggested that the women in Group B that may have fertility challenge are those in subgroup of Group B (AB). Therefore, matured follicular size should be considered with the woman's age. If the follicles grow bigger away from the range for a woman's age, it may be the marker for infertility or reproductive health challenges.

Recommendation

We hypothesize that this large follicle for age may be linked with infertility and possible miscarriages. The IVF studies of Jaime et al. even though did not consider woman's age did suggest that large follicles are linked with low birth rate.^[17] We propose further studies to verify this hypothesis. We recommend that trigger HCG be given to women at the point that will enable them rupture their maximum matured follicles within the sizes that falls below, or exactly on the control line for their age in order to improve their fertility and chances of conception. This suggestion is a simplistic derivation from the graph in [Figure 5]. We recommend that, in case of bigger matured follicles for age with associated high periovulatory estrogen, aromatase inhibitors and anti-low-density lipoprotein cholesterol be given during the periovulatory period to bring the estrogens to the normal range and also control the development of bigger matured follicles for age. Finally, we recommend that cumulus complex study be included during routine ultrasound follicular tracking so as to have a comprehensive anatomical ovulation diagnosis.

Acknowledgment

I would like to thank all the women that volunteered to participate in the Control Group (A). I want to appreciate all the NaPro Medical Consultants of FertilityCare Centers of Africa for their encouragements, and advice for this work. My special thanks to Dr. Wanda Alli-Balogun, MD (CFCMC), for her support and kind review of this work. I thank Professor Thomas W, Hilgers for his mentorship and training. My thanks also go to my wife Mrs Vivian Achebe (FCP), for her prayers and support for this work. God bless you all.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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