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Date of last update: 10/14/2017.

Forum Name: Obstetrics

Question: Luteal Phase Length

 Jessica1189 - Thu Nov 19, 2009 3:40 pm

What is the longest number of days that a luteal phase can possibly be? I have around a 35 day cycle normally and have recently just found out I'm pregnant. I'd like to know when I conceived. Is is possible for luteal phases to be longer than 16 days? I"ve heard both. My last period was October 9th. Thanks!
 Debbie Miller, RN - Mon Nov 30, 2009 11:46 pm

User avatar Hello,
Yes, it is possible for your ovulation day to be day 21 of your cycle with a 35 day pattern. This would mean you could have conceived around October 30.

I hope this helps.
 Jessica1189 - Tue Dec 01, 2009 9:57 pm

Thanks! It does help, but I'm curious about the length of the luteal phase. is it possible for them to be longer than 16 days or not possible? It's a confusing matter! thanks in advance
 Debbie Miller, RN - Sat Dec 05, 2009 10:20 am

User avatar Its true. Each woman is individual and averages take into consideration those with shorter and those with longer cycles and phases. Ovulation does typically occur exactly on day 14 - this is just the median based on a "typical" cycle. It is estimated only about 20% of women actually ovulate on that day and the day of ovulation is what is significant in conception attempts. In most women that will be between day 11 and day 21. This also explains why an "estimated due date" is just that - estimated. We don't know exactly when conception occurred in most cases.

Best wishes.

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