I honestly thought this question was one I'd have trouble answering, but there are literally hundreds (maybe thousands) of forum posts from women asking this same question. If you're single and pregnant what is the best way to deal with sexual needs and desires? There are a few obvious answers, but there are also a few controversial answers – you choose what's best for you.
The number of women asking about masturbation during pregnancy is astounding. Many first-time mothers weigh the moral debate, but they have no shoulders to lean on to talk through the good and the bad. Morally if you masturbated before becoming pregnant, you should feel safe masturbating after pregnancy. Masturbation is not harmful to baby when done right. Don't use foreign objects not designed for the vagina and respect the depth of the vagina when using toys. Lube up to decrease the risk of irritation or infection and make sure to wash your toy between uses.
If masturbation is just not doing it for you – there is always dating. Remember,dating and sex are safe no matter how pregnant you are (unless your doctor has warned you to stop having intercourse for medical reasons). The moral issue in this choice is when is it okay to have sex while single and pregnant? Whether you're pregnant or not you need to use protection to prevent sexually transmitted disease – so unsafe sex is out of the question. But sex is not out of the question. Your personal life revolves around your choices. If you started dating someone early in the pregnancy and you feel content enough with the relationship to move it to the next level there is no reason NOT to have safe sex during pregnancy.
Being pregnant and single does not mean you have to walk through life thinking about, but not having sex. Whether you choose yourself or another partner is a moral choice you'll need to make, but both are safe options with the right methods in mind.