Infertility Concerns: Low Sperm Count & Motility - Seeking Advice

Question
Hi,I am 25 years old and I have a daughter who just turned 13 months. I had a natural miscarriage at 12 weeks in April. My LMP was August 18th. My husband has had a couple semen analysises done in the past and we know that he was low count (10 million every 24 hours or if we abstain close to 30 million every 56 hours) and low motility (30 %). We have also been told that when they did the test that very few sperm were alive after 6 hours... despite this "bad" news we have been able to get pregnant twice. It is important for us to have sex no more than every 48 hours to build up my husband's sperm count. My question is this... How long does it take the sperm once they have been deposited in the vagina to reach the egg? I am always concerned about when is the best time to have intercourse. Should we abstain several days before I ovulate and wait until I get a positive Ovulation predictor test, or should we just go every otherday for the whole cycle until I am sure that I ovulated? Also, would using the lubricant "PreSeed" help extend the life of my husband's sperm? Any help would be greatly appreciated.
Thanks! -Laurie

Answer
If you have a normal 28 day cycle (from the first day of your period until the first day of your next period) ovulation usually occurs on cycle day #14. YOu can ONLY become pregnant if you have intercourse on cycle day #13, 14, 15, or 16 each month. Once the sperm are deposited into the vagina, they rapidly traverse the uterus and the fallopian tube and fertilize the waiting ovum (which is at the end of the tube). It is better to have intercourse at the time of ovulation or one day prior to ovulation. It  is useless to have sex more than two days after ovulation. I would suggest allowing your husband's sperm to build up and time intercourse as close to ovulation as you can. Good luck.