Metformin use during the first trimester of pregnancy. Is it safe?
OBJECTIVE
A pregnant patient with polycystic ovary syndrome asked me whether continuing metformin, which she was taking to treat infertility before her pregnancy, is safe for her fetus. She has heard that metformin is a "drug for diabetes." How safe is it to take metformin during the first trimester of pregnancy and beyond?


CONCLUSIONS
Despite the traditional response that all oral hypoglycemic agents are absolutely contraindicated during pregnancy, evidence that metformin is probably safe during the first trimester of pregnancy and beyond is accumulating. Results of a recent meta-analysis by the Motherisk Program showed no increase in incidence of major malformations and a potential protective effect in this patient population.
Koren
Gideon
G
Gilbert
Cameron
C
Valois
Maria
M
D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008687:Metformin / Q000627:therapeutic use*; D011085:Polycystic Ovary Syndrome / Q000188:drug therapy*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000188:drug therapy*; D011261:Pregnancy Trimester, First; D012449:Safety
D007004:Hypoglycemic Agents; D008687:Metformin