Does ovulation on cd21 of 33 day cycle lower my chances of conception? when should i seek help?

Shorter luteal phase: If you're ovulating on day 21 of a 33 day cycle, the second half of your cycle - the luteal phase, which starts with ovulation and lasts until your next period or pregnancy - is a little shorter than normal. It may affect your chances to conceive. If you're trying to conceive at age 38 see a reproductive endocrinology and infertility (rei) specialist for help after 6 months of trying or sooner.