What Are The Risks Of Birth Defects From Taking Bactrim For A Week At 3 Weeks Of Pregnancy?

Posted on Tue, 14 Aug 2018

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Tue, 14 Aug 2018 Answered on

Thu, 24 Mar 2022 Last reviewed on

Question : I take Bactrim when I was 3 weeks pregnant . I took it for 7 days, twice a day , dose of 160/800 mg. How is the risk of birth defect for the fetus

Answered by Dr. Dr. Rakhi Tayal (36 minutes later)

Brief Answer:
Not likely to affect the baby.

Detailed Answer:

Hello,

At 3 weeks of pregnancy, the fetus has not yet implanted in the uterus and is not in direct contact with the maternal blood circulation. Taking the antibiotic for 7 days is not likely to affect the baby. You can go for a regular antenatal check up and level II scan to confirm this.

I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Wishing you good health.
Regards,
Dr. Rakhi Tayal

Above answer was peer-reviewed by : Dr. Vaishalee Punj

Follow up: Dr. Dr. Rakhi Tayal (38 hours later)

Hello doctor , the beginning of my last menstruation was June-22. I begin taking Bactrim in July 19 until July 25 . But my menstruation cycle is not regular , because the ultrasound show in August 7, that the fetus was 5 weeks . So When I took the antibiotic , does the fetus wasn’t in the uterus or it was already implanted .

Thks

Answered by Dr. Dr. Rakhi Tayal (6 hours later)

Brief Answer:
Details below.

Detailed Answer:

Hello,

You took Bactrim after the fourth week of pregnancy- counting from LMP. It is during the time of implantation. Usually it does not affect the baby so early. And you took it for a short period only. So no need to worry and go for regular antenatal scans as advised by your gynecologist.

Hope my answer is helpful. Do accept my answer in case there are no further queries.
Regards

Above answer was peer-reviewed by : Dr. Arnab Banerjee