 [ Symptoms ] i am using no scarshydroquinone tretinoin mometasone for burn mark will it work and how much time will it take to fade  hello doctor  i accidentally burnt my face with hot iron one month back initially it developed a brown dry patch which after some time i removed till that stage new skin came and there was no scar however after few days a brown scar is developed on that area now i have been using no scars cream hydroquinone trtinoin mometasone for 2 days i want to ask if it is safe to use and will it give results [ Disease ] technically it takes just one sperm to fertilize an egg and achieve a pregnancy but for each sperm that reaches and fertilizes an egg there are many millions that do not the average ejaculation contains close to 100 million sperm and according to the world health organization men who have fewer than 20 million sperm per milliliter of semen may have difficulty conceiving why do you need so many sperm if it takes just one to make a baby because the journey from the vagina to the fallopian tubes through which the eggs travel from the ovaries to the uterus is an arduous one that few sperm survive for those that complete the trip penetration of the egg is far from a sure thing the egg is covered by a thick layer that makes fertilization more difficult experts believe this process may be nature is way of allowing only the healthiest sperm to fertilize the egg thereby providing the greatest chances for a healthy baby