It is estimated that one in five pregnancies will result in miscarriage (termed spontaneous abortion). Given this high percentage, one would expect the medical profession to have more insight about etiology, treatment and prevention of miscarriage. When I was in my OB/GYN training we were told that the majority of miscarriages are the result of chromosomal abnormalities. Many of the studies surrounding this issue were conducted in the early 1980s, and I question this information since most women who have miscarriages do not have the products of conception sent for chromosomal analysis and the majority of them go on to have a subsequent normal pregnancy.
Certainly we would expect as more older women (late 30s-40s) are pursuing pregnancy, that age-related chromosomal abnormalities would explain the increased risk of miscarriage in this group. In a study of pregnancies achieved with in-vitro fertilization, the rate of miscarriage was 11.4% in women aged 33-34, 19.8% for women aged 38-40, 29.9% for women aged 41-42, & 36.6% for women older than 42 years.
As a hormone specialist, I recognize that hormonal imbalances and abnormalities abound, are often undiagnosed, and are inadequately addressed before, during and after pregnancy. Knowing that these imbalances impact fertility, I suspect that those numbers cited above reflect an increased percentage of hormonal problems in those women seeking treatment for infertility. While there are clearly medical & structural abnormalities which can cause miscarriage (which I’ll outline later), the medical profession generally does not conduct a work-up on a woman until she’s considered to have recurrent miscarriages, defined as three or more consecutive miscarriages. I’m of the opinion that searching should begin after one miscarriage and work-up should definitely be done after two as my philosophy is toward proactivity and prevention. I never want a woman to needlessly suffer a painful loss if an answer can be found. From a common-things-being-common perspective, I generally want to assess a woman for progesterone deficiency (also called luteal phase deficiency) and thyroid abnormalities. The most important step for a woman is to chart her cycles so we can get some idea of which direction to focus our efforts. Blood work can be taken for thyroid assessment and other medical problems like blood sugar abnormalities.
Luteal phase deficiency (LPD) is somewhat controversial in the field of OB/GYN. This is mostly because the diagnosis was originally made by an endometrial biopsy that was “out of phase” with where the patient was in her menstrual cycle or luteal phase. The first half of the cycle after menses is called the follicular phase which tracks the development of a follicle in preparation for ovulation, a phase that is dominated by estrogen. The second half of the cycle after ovulation is called the luteal phase, reflecting the production of progesterone by the corpus luteum (ovulated egg). While the majority of women have a stable luteal phase of 13-14 days, there is some variability and there are clearly women who have a shortened luteal phase of 6-7 days. Accurately assessing progesterone levels because of irregular cycles or shortened luteal phases contribute to the difficulty of making the diagnosis of LPD.
Dr. Thomas Hilgers is Clinical Professor of the Department of Obstetrics and Gynecology at Creighton University School of Medicine in Omaha, NE. He is also Director of the Pope Paul VI Institute for the Study of Human Reproduction and in my opinion, is the foremost authority of the hormonal influences on fertility and pregnancy. He outlines the 3 most common luteal phase deficiencies in his textbook The Medical and Surgical Practice of NaProTECHNOLOGY (‘the term ‘NaPro’ refers to ‘Naturally Procreative’), based on a study of 328 patients with infertility.
Type I: The post-Peak phase is short (less than or equal to 8 days in duration) estimating a short luteal phase. The last progesterone level prior to the onsent of menstruation is less than or equal to 2.0 ng/mL.
Type II: The post-Peak phase is normal in length but the progesterone profile (Peak +3,5,7,9, & 11) is clearly suboptimal.
Type III: The post-Peak phase is normal in length but the progesterone profile (Peak +3,5,7,9 & 11) shows an abrupt drop (>50% drop of Pk+9 and Pk+11)
Most women who have progesterone levels assessed have them drawn as a cycle day 20 blood draw. Type I & II deficiencies will have a Peak+7 decreased progesterone level, but this blood draw will miss a type III luteal phase deficiency. While efforts can be made to make a diagnosis of luteal phase deficiency, the difficulty of doing so should not preclude the use progesterone therapy in a subsequent pregnancy. If a woman has evidence from charting of a possible luteal phase deficiency, I would strongly suggest finding a provider who would be willing to prescribe progesterone even in the absence of a definitive diagnosis.
By far the most common hormonal disorder I see is Polycystic Ovarian Syndrome (PCOS). PCOS is characterized by insulin resistance, excess androgens (“male” hormones) often causing acne, hair growth on the face and infrequent/decreased ovulation. Since progesterone is made from the ovulated egg, virtually all PCOS patients are progesterone deficient.
Many doctors still don’t believe in the benefit of progesterone therapy in the first trimester for the prevention of miscarriage (I had one colleague refer to it as “voodoo medicine”) due to conflicting studies and some of the diagnostic pitfalls outlined above. I believe a return to the basics of human reproduction and a lack of side effects with bioidentical progesterone should quell any fears. Progesterone is the PRO-GESTATIONAL hormone. Without it, you cannot get pregnant; without enough, you cannot stay pregnant. Babies literally take a bath in progesterone for the entire pregnancy. It is an essential hormone to every aspect of reproduction. The literature is now abounding for the use of progesterone therapy in women with a history of preterm birth. Much has been said about how much money could be saved in the care of premature babies in the face of this one intervention. Why then are we so reluctant to undertake the larger studies needed for the routine first trimester application of progesterone therapy in those women at higher risk? Fertility doctors know the importance of progesterone which is why all of their patients are automatically given it. My approach is to either test or treat empirically. If a woman with a history of miscarriage is able to undertake hormonal testing prior to another pregnancy, efforts should be made to exclude any hormonal abnormalities. If there is any evidence of abnormality through testing or charting, I recommend using progesterone therapy at least through 14 weeks when the placenta takes over production of progesterone.
Dr. Hilgers published data of normal progesterone levels for every gestational week of pregnancy, so my practice is to test progesterone before discontinuing it. I also do not see a reason to not give a woman progesterone if she finds herself pregnant again before hormonal evaluation can take place. I tell these women, “Progesterone deficiency may not be the cause of your miscarriage, but it can’t hurt to take it and it may help prevent a miscarriage.” I follow up this treatment by monitoring their progesterone levels.
Besides luteal phase defect and thyroid disorders, there are certain other medical conditions that have been associated with a greater risk of miscarriage. These include:
• Lupus and other autoimmune disorders
• Heart disease
• Severe kidney disease, especially when there is also high blood pressure
• Familial or acquired clotting disorders
• Celiac disease
Other factors that can cause miscarriage are
• Intrauterine or intraamniotic infections
• Drug use, excessive alcohol intake
• Acquired (adhesions, fibroids) or congenital uterine defects (septation, bicornuate uterus, etc)
• Incompetent cervix
Depending on the results of risk factor assessment in the individual woman with two or more miscarriages (my choice is 2 rather than 3), consideration can be given to a more targeted blood work-up, ultrasound, HSG (hysterosalpingoram: dye study of uterus and ovaries), chromosomal testing of parents, and possibly hysteroscopy/laparoscopy. I strongly encourage women to read, educate and research their options and partner with a health care provider who is willing to explore those options with them.
Dr. Poppy Daniels is an Ob/Gyn who diagnoses and treats a wide spectrum of hormonal issues across all age groups. She has a holistic approach utilizing bioidentical hormone therapy, nutrition and targeted supplementation. She is also a natural birth and VBAC advocate, and supports a birth model incorporating collaborative physician/midwifery care. Visit her at www.drpoppy.com, “Dr. Poppy” on Facebook, and@drpoppyBHRT on Twitter.