Hey N.,
I'm a certified personal trainer so I will respond to the exercise portion of your question. I'm not a certified 'sexpert' so I won't go there...though I do believe it's fine to have sex while pregnant unless your midwife tells you otherwise!
Exercise is great during pregnancy and can help make your delivery and recovery easier as well. As one other woman mentioned, keep your heart rate at 140 beats per minute or below. The reason behind this is that if your heart is beating too fast, more blood will flow to the heart and lungs and less to the uterus. If you are really fit, you can possibly go above 140, but ONLY WITH YOUR DOCS APPROVAL!! Check with them first. After the first trimester to not perform exercises in the supine position(on your back) again the weight of the baby can restrict blood flow to the uterus or cause restricted blood flow to the mother causing dizziness, etc. It is fine to lift weights/resistance training, HOWEVER, you will want to decrease your weights. Your bones, joints and ligaments shift during pregnancy which may fool you into believing you can lift more than you really should which will result in injury. My advice would be to perfom strength training on machines versus free weights as it is safer during that time. You should be able to do about 20 reps before fatiguing. Make sure to stretch, but again, don't overdo it. You may find yourself more flexible during pregnancy due to the hormone relaxin, but again, if you push the limits you could hurt yourself. Other than that, hydrate, hydrate, hydrate!!
Below is a good program to follow:
Walking(30-45 minutes 3-5x/week)heart rate 140 or below
Strength train(2x/week.)best to perform a full body routine, starting with largest muscle groups. 20 reps per machine
Flexibility(3-5x/week...or following each exercise session)
email me for more advice
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