Senior Consultant, Medical Genetics, Artemis Hospitals, Gurgaon, India
Part 7 of 12 in Finding Answers in Recurrent Pregnancy Loss
Endocrine Causes: Thyroid, PCOS, and Diabetes in Recurrent Pregnancy Loss
June 7, 2026
Untreated thyroid disease is an important and readily treatable cause of recurrent pregnancy loss; Dr. Singh recommends keeping TSH below 2.5 in women trying to conceive or with a history of loss, titrating levothyroxine to that target, though if there's no overt hypothyroidism and only TPO antibodies are positive, treatment generally isn't indicated. Polycystic ovarian syndrome causes recurrent loss as well as infertility, driven by poor oocyte quality, and uncontrolled diabetes both raises loss risk and can cause birth defects, making good glycaemic control essential.
Hyperprolactinaemia (especially with a history of galactorrhoea, anovulatory or prolonged cycles, or difficulty conceiving) should be tested for and treated with bromocriptine when confirmed. For PCOS or insulin resistance, metformin has a genuine beneficial role: started 2-3 months before conception, it's safe to continue into pregnancy and is monitored with regular GTT, HbA1c and blood sugar checks.
This guide is based on a live Jivo Masterclass — Dr. Kanika Singh taught doctors across Africa on June 7, 2026.
FROM THE LIVE Q&A
Dr. Isaya
My question is about sperm collection. In my clinic I often see couples where the male is over 50 years old. What are the chances of getting good quality sperm, and what are the implications for implantation?
Dr. Kanika Singh
I will not be able to give you details about specific sperm selection procedures, as in our hospital this is a multidisciplinary process involving the IVF specialist and the andrology laboratory. But in terms of the genetic implications: above the age of 50, there is a high chance that sperm quality is reduced, and the sperm DNA fragmentation index is likely to be elevated. Unless we specifically test for it, we do not know the exact level, but even without testing, there is a significant chance that sperm DNA quality is impaired, which can result in recurrent pregnancy loss or implantation failure. Testing the sperm DNA fragmentation index in men above 50 with a history of recurrent pregnancy loss or implantation failure would be worthwhile.
Frequently Asked Questions
For patients with PCOS, how long should metformin be taken before conception and after conception?▼
Metformin should be started at least 2 to 3 months before conception. It is safe to continue in pregnancy and is generally continued through the first trimester and sometimes beyond. It should be monitored with GTT as well as regular HbA1c and blood sugar checks throughout.
My question is about sperm collection. In my clinic I often see couples where the male is over 50 years old. What are the chances of getting good quality sperm, and what are the implications for implantation?▼
I will not be able to give you details about specific sperm selection procedures, as in our hospital this is a multidisciplinary process involving the IVF specialist and the andrology laboratory. But in terms of the genetic implications: above the age of 50, there is a high chance that sperm quality is reduced, and the sperm DNA fragmentation index is likely to be elevated. Unless we specifically test for it, we do not know the exact level, but even without testing, there is a significant chance that sperm DNA quality is impaired, which can result in recurrent pregnancy loss or implantation failure. Testing the sperm DNA fragmentation index in men above 50 with a history of recurrent pregnancy loss or implantation failure would be worthwhile.
What TSH level should be targeted in women with recurrent pregnancy loss?▼
TSH should be kept below 2.5 in women trying to conceive or with a history of loss, titrating levothyroxine to that target.
Should TPO antibody positivity alone be treated?▼
If there is no overt hypothyroidism and only TPO antibodies are positive, treatment generally isn't indicated.
How does polycystic ovarian syndrome contribute to recurrent pregnancy loss?▼
PCOS causes recurrent loss as well as infertility, driven by poor oocyte quality.
When should hyperprolactinaemia be tested for and treated?▼
It should be tested for, especially with a history of galactorrhoea, anovulatory or prolonged cycles, or difficulty conceiving, and treated with bromocriptine when confirmed.
Why does uncontrolled diabetes raise the risk of recurrent pregnancy loss?▼
Uncontrolled diabetes both raises loss risk and can cause birth defects, making good glycaemic control essential.
In This Series: Finding Answers in Recurrent Pregnancy Loss
- 1.Finding Answers in Recurrent Pregnancy Loss
- 2.Fetal Chromosomal Abnormalities: The Leading Cause of First-Trimester Loss
- 3.Balanced Translocation: When a Genetically Normal Parent Passes on Recurrent Loss
- 4.Single-Gene Causes: Why Second-Trimester Losses Need a Different Genetic Workup
- 5.Anatomical Causes: Uterine Septum, Fibroids, and Cervical Incompetence
- 6.Antiphospholipid Antibody Syndrome: Diagnosis and Treatment
- 7.Endocrine Causes: Thyroid, PCOS, and Diabetes in Recurrent Pregnancy Loss
- 8.Sperm DNA Fragmentation: The Male Factor in Recurrent Pregnancy Loss
- 9.The Immunological Debate: NK Cells, TNF-Alpha, and IVIG Therapy
- 10.What to Test For: A Practical Investigation Framework by Trimester
- 11.Pre-Implantation Genetic Testing: PGT-A, PGT-M, PGT-SR and PGT-HLA Explained
- 12.Prognosis After Recurrent Pregnancy Loss: Why the Outlook Is Better Than Most Couples Expect